/var/log/upstart/ureadahead.log contains garbage

Status changed to 'Confirmed' because the bug affects multiple users.

Same here, although the boot seems a lot slower than quantal was.

ureadahead itself hasn't changed in any significant way for a long time now, so this is looking like a possible kernel issue.

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1085766

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.8 kernel[0] (Not a kernel in the daily directory) and install both the linux-image and linux-image-extra .deb packages.

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.8-rc2-raring/

After testing the mainline kernel, we can perform a kernel bisect to try and identify the commit that introduced this regression.

Problem is seen on i386 and amd64, but NOT on armhf (panda ARMv7).

I tried this using ...

linux-headers-3.8.0-999_3.8.0-999.201301110405_all.deb
linux-headers-3.8.0-999-generic_3.8.0-999.201301110405_i386.deb
linux-image-3.8.0-999-generic_3.8.0-999.201301110405_i386.deb
linux-image-extra-3.8.0-999-generic_3.8.0-999.201301110405_i386.deb

... however, removing the pack file and rebooting resulted in the following in /var/log/upstart/ureadahead.log:

Counted 1 CPUs

ureadahead: Error while tracing: No such file or directory

This seems to be because the mainline kernel does not enable /sys/kernel/debug/tracing/events/fs/*.

Looking more closely at my /var/log/upstart/ureadahead.log, this looks like memory corruption:

ureadahead:^P^P_í,<8b><97>¿add): Ignored relative path
ureadahead:^P^P_í,<8b><97>¿irqd: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿er/0: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿er/0: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿er/u: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿er/u: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿tion: Ignored relative path
ureadahead: ^P^P_í,<8b><97>¿h) S: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿sche: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿hdog: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿hdog: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿tirq: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿atio: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿ker: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿ker: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿hdog: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿tirq: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿atio: Ignored relative path
ureadahead:^P^P_í,<8b><97>¿ker: Ignored relative path

If you squint you can make out what appear to be partial kernel thread names:

hdog => watchdog/...
tirq => ksoftirqd/...
atio => migration/...

etc.

There are two issues. ureadahead is using a deprecated and now removed interface to ftrace to enable tracing. The kernel interface for open has changed the type of the filename, producing junk for filenames.

This bug was fixed in the package ureadahead - 0.100.0-13

---------------
ureadahead (0.100.0-13) raring; urgency=low

  * src/trace.c: tracing_enabled is deprecated and gone, switch to tracing_on
    (LP: #1085766).
 -- Andy Whitcroft <email address hidden> Fri, 11 Jan 2013 12:05:17 +0000

This bug was fixed in the package linux - 3.8.0-0.3

---------------
linux (3.8.0-0.3) raring; urgency=low

  [ Andy Whitcroft ]

  * Revert "SAUCE: (no-up) trace: add trace events for open(), exec() and
    uselib()"

  [ Scott James Remnant ]

  * SAUCE: (no-up) trace: add trace events for open(), exec() and uselib()
    (for v3.7+)
    - LP: #1085766, #462111
 -- Andy Whitcroft <email address hidden> Fri, 11 Jan 2013 16:57:27 +0000

Please could you submit a patch to kernel 3.7.2 so that people like me, that like to compile vanilla kernel, can enable ureadahead tracing?
Thanks
Gianluca

The verification of this Stable Release Update has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regresssions.

same problem in 15.04 again

And the same problem in Kubuntu 15.10, I think the fix may be the same.

This problem seems to exist currently on both 15.10 and Xenial

I can confirm i am having the same issue on Xenial, my syslog gets flooded with millions of ureadahead messages, i restarted and i havent seen it happen as yet again. This usually happens when you start up the PC.

What is ureadahead??

I have this too with Xenial. Looking at yesterday's syslog:

$ sudo grep -c "Ignored relative path" /var/log/syslog.1
19728

and here are the first few lines:

$ sudo grep -m30 ureadahead /var/log/syslog.1
Oct 6 08:00:20 dl1 systemd[1]: Stopped Stop ureadahead data collection 45s after completed startup.
Oct 6 08:01:02 dl1 systemd[1]: Started Stop ureadahead data collection 45s after completed startup.
Oct 6 08:01:47 dl1 systemd[1]: Starting Stop ureadahead data collection...
Oct 6 08:01:47 dl1 systemd[1]: Started Stop ureadahead data collection.
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:events/fs/open_exec/enable: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:buffer_size_kb: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:tracing_on: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:binfmt_misc: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:size: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:start: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:size: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:start: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:size: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:start: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:size: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:start: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:size: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:start: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:dm/uuid: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: message repeated 11 times: [ ureadahead:dm/uuid: Ignored relative path]
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:.: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:1/stat: Ignored relative path
Oct 6 08:01:47 dl1 ureadahead[222]: ureadahead:1/cmdline: Ignored relative path